I. Field of the Invention
The present invention relates generally to exercise equipment and more particularly to P.S.I. Nordic Track, of Chaska, Minn., under the mark NORDIC TRACK, ski machines and devices used in setting arm resistance levels on such equipment.
II. Description of Prior Art
Over the last few decades, a variety of medical and scientific advancements have reinforced the fact that frequent exercise can have tremendous health benefits. As a result, millions of persons have joined health and fitness clubs and purchased home exercise equipment. Some of the more popular types of exercise devices are of the cross-country skiing variety, particularly the ones manufactured by Nordic Track, Inc. Those devices generally comprise a pair of ski-like members which move relative to a frame, while a pair of rope-like extensions are pulled against a resistive force in coordination with the motion of the ski-like members. The resistance to arm movements is provided by a spring-loaded reaction member which is frictionally coupled to a rotatable drum on the exerciser, wherein the resistance to rotation is provided by tightening a threaded nut against the drum and the spring-loaded reaction member.
One version of the resistance indicator of the prior art is shown in U.S. Pat. No. 4,728,102, issued to Pauls, the disclosure of which is incorporated herein by reference. While this device does permit adjustment of the resistive force, there are a number of apparent deficiencies which are a result of its particular construction. First, the use of a moving needle against a marked plate does not provide a static resistance indication because the nut has to be adjusted through trial and error during exercise until the resistance needle indicates a satisfactory level. Once the setting is made, the level itself is not precise, because the needle can only indicate the maximum resistance while the user is exercising. Moreover, because of the analog nature of the Pauls device, one's perception of where the needle is depends on viewing angle and lighting conditions. These deficiencies are especially problematic when two or more persons use the exercise device, because the nut position and resistance must be adjusted between users with no repeatability of resistance for any given user. Consequently, the sequence of rough and fine adjustments each time the exercise device is used tends to detract from the overall exercise effectiveness because each user must stop and adjust the nut several times before finding his or her desired resistance setting. Finally, it is a common practice among persons who exercise to gradually increase the resistance as their upper body strength increases over time. Although the Pauls device can be adjusted, it is difficult to ascertain small differences in resistive force from one session to the next due to the coarse nature of indication by use of large springs.
Therefore, a more precise means of setting resistive force, such as a digital indicator, would result in more accurate settings, greater repeatability of settings between exercise sessions, and less frustration to the user by the elimination of trial and error methods of establishing a particular resistance setting. Furthermore, the setting can be applied before exercise begins, saving time for the exerciser. The proposed Preset Digital Resistance Indicator may be used in addition to the Pauls device.